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By M. Karmis

The Virginia Center for Coal and Energy Research is leading an interdisciplinary coalition to identify potential carbon sequestration sinks in unmineable coalseams as part of the U.S. Southeast Regional Carbon Sequestration Partnership. The Virginia Center for Coal and Energy Research and the Eastern Coal Council are leading education efforts for the project, as well as specific outreach efforts in Central Appalachia in order to develop a process for stakeholder education and engagement in sustainable energy.

Jan 1, 2007

By Russell G. Slayback

Feasibility investigations for prospective gold mines too often neglect to consider ground water. Simple observations and tests during drilling exploration can provide useful data on probable water conditions. As the prospect becomes more serious, more detailed investigation of ground water and dewatering needs may be warranted. Ignoring ground-water conditions can lead to costly mistakes.

Jan 1, 1987

By Bob Newbery, Kenneth W. P. Eng. Kolthammer

SUMMARY Reference is made to the reasons for drying and the equipment is described that is available from which the engineer can make a selection. The factors affecting this decision are described. In the case of drying, design and sizing are ultimately developed empirically and no theoretical approach has been advanced.

Jan 1, 1986

By Luis Tavares Ribeiro

Dynamic programming is based on the-, application of a simple property formulated by Bellman in his principle of optimality (Bellman, 1957): "An optimal policy has the property that whatever the initial state and initial decision are, the-remaining decisions must constitute an optimal policy with regard to the state resulting from the first decision". The method is charaterised by: (Dowd, 1979) a) A function defining the total value at each decision time of the system. b) The set of permissible decisions. c) The present state of the system. d) The number of steps remaining before the procedure is terminated.

Jan 1, 1982

After a discussion of the principles of heavy-mineral enrichment and the sedimentary history of shelf sediments, four models are described that can explain the genesis of heavy-mineral deposits in shelf areas. On the basis of these models, the heavy-mineral potential of most shelf areas is estimated to he significantly lower than the potential of their neighboring coastal plains.

Jan 1, 1991

By A. D. Shuloyakov, V. A. Zukerman, G. A. Finkelstein, V. I. Kurets

Possibilities of electric pulse disintegration are discussed with emphasis on high selectivity of the process as compared to mechanical comminution methods especially when applied to polymineral ores. Physical explanation of this phenomenon is suggested. The authors present results of some experimental tests illustrating regularity of this phenomenon irrespective of origin of ores or dissemination pattern of valuable minerals including both dissipated and accessory minerals. Some operating plants applying this principle are described the plants used either for mineral research purposes or for obtaining pure monomineral fractions or for treatment of gems to be faceted. Obstacles for implementation of this technology are mentioned.

Jan 1, 1995

By Y. Nan

A new computer simulation model for the analysis of underground coal mine production systems in the Peoples Republic of China is presented. As a case study the model was used to analyse the railway system of an existing underground coal mine. Some results of this first application are given in this paper and some conclusions of common interest for underground rail haulage systems are discussed.

Jan 1, 1986

By William E. Souder, R. J. Evans

From time to time, major technological innovations arise that alter the time-honored ways of doing things. Such innovations can dramatically benefit society in terms of new products, increased outputs, reduced costs and general modernizations. However, the advent of these types of technologies is likely to be resisted because of their uncertain potentials, and because they disrupt established routines and industry patterns. This paper reviews the case history of water jet coal cutting, and assesses its potential to become a major innovation within the next decade.

Jan 1, 1983

By J. I. Schoenherr, T. A. Baloun

Mixed cable waste, which amounts to more than 200,000 tpy in Germany, is subjected to recycling. In most cases cable recycling means only recovering copper and/or aluminum metals. The remaining cable waste contains nearly 3-8% of the reusable materials, and is disposed of in landfills. Aluminum is recovered within copper products and leads to lower product prices. Preliminary laboratory tests show that the use of shaking hydro-tables as well as electrostatic separators result in less than 1 % of metals in the residual material. The products are high in grade at metal recoveries of more than 85%. Furthermore, applying a modified electrostatic separator may also lead to an efficient Cu-Al separation. The separation efficiency amounts to up to 95%.

Jan 1, 2002

By P. R. Khangoankar, S. Devasahayam

An experimental study of the particle charac¬teristics of the magnesium carbonate crystals formed by the reaction between magnesium chloride and sodium bicarbon¬ate at different temperatures is described. The rate of growth of magnesium carbonate crystals for any constant tempera¬ture is established, and this rate of growth is related to the degree of supersaturation at the given temperature. The activation energy calculated using empirical constants de¬rived from the relationship between the crystal growth rate and supersaturation, is indicative of a surface-reaction mechanism.

Jan 1, 1996

By I. Iwasaki, H. Dho

Two aromatic-type chelating agents, 1,10 phenanthroline (phen) and 8-quinolinol (quip), were tested as specific depressants for magnetite in the cationic silica flotation of magnetic taconite concentrates. Micro and batch flotation tests, along with zeta potential and adsorption measurements, were used. In the presence of a cationic collector, dodecylammonium chloride (DAC), the Fe/phen surface chelate electrostatically repelled DAC, and the magnetite was depressed. The negatively charged Fe(quin)2(OH)2- on the magnetite surface attracted the cationic collector and made magnetite floatable.

Jan 1, 1997

By T. W. Camm

In this US Bureau of Mines report, mine and mill cost models are presented to make estimates of the cost to develop mineral deposits in the desert region of the southwest United States. Regression analysis was used to generate capital and operating cost equations for each model based on daily production capacity. These models are used for Potential Supply Analysis (PSA) studies by the Bureau, which analyzes the economic benefits of minerals in a region.

Jan 1, 1995

By Mary Fu, Helen Leung, Colin R. Phillips

In uranium mines, the median size of the aerosol has been found to be about 0.1 micron or less. Such small aerosols are readily deposited or "plated-out" on dosimeter interior surfaces resulting in the recording of a low dose. The "plate-out" properties of the CEA alpha dosimeter head are described with respect to aerosol properties in controlled experiments in the laboratory. A simple model is derived to estimate the amount of "plate-out" in the CEA head.

Jan 1, 1981

By Andy J. Robinson, Mark D. Claassen

Railroad companies and transit authorities have been slow to acknowledge that for many—utility crossings, a direct pipe installation below live rail can be just as effective as a more intrusive traditional cased crossing. Properly designed and specified pipe jacking work, and specifically pressure-balanced microtunneling, coupled with careful specification and analysis of geotechnical monitoring and, where necessary, ground improvement measures, can produce a low-risk, low ground movement solution to the needs of utility companies and municipalities whose services need to pass below urban and rural rail corridors. This paper discusses the design, geotechnical and ground improvement aspects of microtunnel crossings below active heavy and light rail lines and crossings beneath active subway tunnels.

Jan 1, 2003

By Edward C. Dowling

Dilbert, management mumbo-jumbo, and human resource buzzwords aside, this paper defines corporate culture and why it is important to understand it. The sum of company experience, both good and bad, defines the way people work together. This integration of experience outlines the expected behaviors, or culture, in an organization. Given the competitive pressures inherent to our industry, the dizzying ongoing industry restructuring, and the recognition that behaviors drive effectiveness, the appreciation of an organization's culture is a prerequisite to meaningful improvement, particularly for those organizations undergoing growth, acquisitions, or mergers.

Jan 1, 2001

By S. J. Porter, M. T. McRae

The Melbourne City Link project includes two three-lane highway tunnels, 1.6 and 3.4km long, respectively, which are both approximately 16 meters wide and 9 meters high. The tunnels will be excavated through interbedded, moderately to highly jointed siltstones and sandstones of the Silurian Age Melbourne Mudstone formation over the major parts of their lengths. The strength of the intact rock varies from less than 5 MPa to greater than 70 MPa. Based on the available information regarding the performance of large span tunnels in weak rock, it was considered that the commonly applied empirical design guidelines for tunnel support, based on rock mass classification systems, should be augmented by more explicit design methods. The support design was, therefore, validated by analytical procedures, including numerical analyses, which are described in this paper.

Jan 1, 1997

By Lynton S. Land

Representative collections of recent dolomites, and of samples concentrated by leaching-out of coexisting magnesian calcites, provide grounds for appraisal of the compositions and cation ordering in recent dolomitized sediments. Unit cell volumes for near-stoichiometric compositions exceed those of ordered dolomite and increase as the departures from regular cation order became more pronounced. Infrared absorption maxima of disordered examples occur at perceptibly lower frequencies. Stable isotope ratios indicate that best ordered examples formed in highly saline environments. Present observations are qualitatively reconciled with data from synthetic products described by other authors.

Jan 1, 1972

By J. M. Keating, R. L. Wiegel

Those processing plants which depend on flotation for their mineral separations are always looking for reagents which are cheaper, more selective or in some other way may provide improved economic performance. This paper describes the rationale for and some results from applying a statistically based approach to reagent testing in those flotation plants which still rely on experienced operators for manual flotation control.

Jan 1, 1986

By Graham G. W. Mustoe, Andrew I. Hustrulid

An advanced numerical model based upon the Discrete Element Method (DEM) has been developed to provide the engineer with unique detailed information to assist in the design of transfer points in large industrial conveyor systems in mining operations. This modeling technique provides a quantitative description of the bulk solids movement through the transfer point. This information consists of the velocity distribution of the bulk solids and the stresses within the bulk solids. The DEM model also gives detailed information concerning the impact forces acting on the transfer structure and the conveyor belts from the bulk solids flow.

Jan 1, 1996

By H. J. Zhang, W. Wui

With the adoption of market-oriented economic policies, Chinese non-ferrous metals industry has gained remarkable progress. The continuously increasing domestic demand for non-ferrous metals, however, calls for more import of raw materials in short supply, such as copper concentrate and bauxite. As an alternative for balancing the shortage and assurance of more stable mineral supply, direct investment in oversea mining project has come to the agenda. This paper discusses the computer-assisted method used for evaluation and comparison of potential mining projects.

Jan 1, 1996